Field of the Application
The application generally relates to Short Message (SM) delivery in a wireless communication environment, and more particularly, to apparatuses and methods for reducing paging for Extended Discontinuous Reception (EDRX) Mobile Station (MS) to receive Mobile Terminated (MT) SMs.
Description of the Related Art
With growing demand for ubiquitous computing and networking, various wireless technologies have been developed, including Global System for Mobile communications (GSM) technology, General Packet Radio Service (GPRS) technology, Enhanced Data rates for Global Evolution (EDGE) technology, Wideband Code Division Multiple Access (WCDMA) technology, Code Division Multiple Access 2000 (CDMA-2000) technology, Time Division-Synchronous Code Division Multiple Access (TD-SCDMA) technology, Worldwide Interoperability for Microwave Access (WiMAX) technology, Long Term Evolution (LTE) technology, LTE-Advanced (LTE-A) technology, and Time- Division LTE (TD-LTE) technology, etc.
Taking the WCDMA technology as an example: the technique called Extended Discontinuous Reception (EDRX) was first introduced for saving power in release 12 of the 3rd Generation Partnership Project (3GPP) specification TR 23.770. The EDRX aims to extend the DRX cycle for a longer period of time, in which a Mobile Station (MS) only has to stay active for a very short time and then enters the inactive state for the rest of the time in the DRX cycle. This greatly reduces power consumption of the MS, especially when the MS is a Machine Type Communication (MTC) device which is powered by a battery and most of the time, it's hard to charge or replace the battery.
For example, the length of an EDRX cycle may be configured from 30 seconds to several minutes long. However, there may be a situation where many SMs terminated for the MS may arrive in the inactive duration (or may be referred to as sleep or “OFF” duration) of the EDRX cycle. Conventionally, the MT SMs will be queued in the Short Message Service (SMS) center in the WCDMA network. When the MS enters the active state (or may be referred to as “ON” duration) from the inactive state, the WCDMA network may page the MS and send the queued SMs to the MS. That is, the conventional design requires certain paging resources of the WCDMA network, not to mention that the delivery of the MT SMs may be greatly delayed due to the long inactive duration of EDRX.
Thus, it is desirable to have a more efficient way of delivering MT SMs to an MS operating in the EDRX mode.